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Annalisa Cabras Maria A. Mannoni Salvatorica Serra Anna Andolfi Michele Fiore Antonio Evidente 《European journal of plant pathology / European Foundation for Plant Pathology》2006,115(2):187-193
Sphaeropsis sapinea was repeatedly isolated in Sardinia from symptomatic samples of the upper part of declining pine (Pinus radiata) plants. Observed symptoms mainly consisted of foliage chlorosis, drying of needles and cankers on branches. The S. sapinea strains were shown to produce phytotoxic metabolites in culture filtrates. Three metabolites were isolated for the first time from this fungus and identified by their spectroscopic and optical properties as R-(−)-mellein, (3R,4R)-4-hydroxymellein and (3R,4S)-4-hydroxymellein. When assayed for phytotoxic and antifungal activities on host and non-host plants and on some phytopathogenic fungi, the R-(−)-mellein showed significant activity, while the other two 3,4-dihydroisocoumarins showed only a synergic activity in both tests. 相似文献
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Phaeomoniella chlamydospora (Pch) and Togninia minima (Tmi) produced scytalone, isosclerone and pullulans in liquid cultures, as well as in calli. Secondary metabolites and host defense compounds were shown to occur in calli of Vitis vinifera cv. Italia and cv. Matilde infected by the esca-associated fungi Pch, Tmi and Fomitiporia mediterranea (Fme). Calli of both cvs. were grown as dual cultures with Pch, Tmi and Fme. The fungi grew well in the presence of calli of both cvs., but callus growth was reduced. Accumulation and changes of total phenolics and recurring phenolics, and of two phytotoxic pentaketides and pullulans were analyzed by HPLC. On comparing results for cv. Italia and cv. Matilde, it can be seen that concentrations of phenolics are strongly related to the cv. The paper discusses the possible relationship between melanin biosynthesis in Pch and Tmi, which utilize pentaketide metabolites as intermediates and their pathogenicity related to phytotoxity of scytalone and isosclerone. 相似文献
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Genchi C Rossi L Cardini G Kramer LH Venco L Casiraghi M Genchi M Agostini A 《Veterinary parasitology》2002,110(1-2):85-91
The authors report the efficacy of an injectable, moxidectin sustained release (SR) formulation for the prevention of canine heartworm infection in endemic areas in northern and central Italy. Three field trials were carried out on a total of 324 dogs. Two hundred forty-three dogs were treated with moxidectin SR 6 months apart and 81 dogs (positive controls) with moxidectin tablets given monthly for 5 consecutive months during the risk season each year throughout the study. Results of testing for microfilariae and circulating adult female antigens were negative for all the experimentally treated dogs at the 6, 7, 11 and 19 months after the last injection. No adverse reactions to moxidectin SR were observed but a moderate pain at palpation and swelling (5-6 cm) at the injection site after the first treatment. In the study areas, prevalence of Dirofilaria immitis infection calculated by testing dogs which had no preventive treatment in the previous transmission season ranged from 33 to 63%. This study confirms the efficacy and safety of injectable, moxidectin SR formulation in the prevention of heartworm infection in dogs and demonstrates that the prophylactic efficacy lasts for the full season and strongly suggests that the product gives 1-year protection. 相似文献
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F. Tenllado I. García-Luque M.T. Serra J.R. Díaz-Ruíz 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(3):235-243
We previously reported a procedure for identifying pathotypes of the tobamoviruses infecting the L-resistant genotypes of pepper based on the polymerase chain reaction (PCR) (Tenllado et al., 1994). We have now used this method to assess pathotype incidence in virus isolates from field pepper samples representing three successive epidemic episodes in southeastern Spain, and to analyse the interaction of pathotypes during experimental infections in pepper plants. The majority of virus isolates corresponded to the P1,2 pathotype, and only three out of twenty behaved as P1,2,3 pathotypes. Interestingly, restriction enzyme analysis of the PCR-amplified products distinguished two restriction subgroups on each P1,2 and P1,2,3 pathotype, referred to as restrictopatterns I1 and I2 or II1 and II2, respectively. Experimental coinoculations of pepper plants with mixtures of two different pathotypes showed coexistence between them when inoculations proceeded simultaneously. However, reciprocal cross-protection was observed between P1,2 and P1,2,3 pathotypes when they were successively inoculated, while no cross-protection was observed between P1 and either P1,2 or P1,2,3 pathotypes. The potential of the PCR-based method for detecting heterogeneity within P1,2 and P1,2,3 pathotypes, and the possibility of genetically engineered resistance to those viruses by genetic transformation with viral coat protein genes are briefly discussed. 相似文献
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Petrosillo Irene Valente Donatella Pasimeni Maria Rita Aretano Roberta Semeraro Teodoro Zurlini Giovanni 《Landscape Ecology》2019,34(10):2213-2228
Landscape Ecology - In the last 30 years, the number of golf courses has increased dramatically worldwide. Since no other sport occupies and manages such large areas of green space, landscape... 相似文献